The present invention relates to a packaging system for shipping rolls of material and to an improved support and spacing structure for use in the system.
The U.S. Pat. No. 4,195,732 (Bell), which is assigned to the assignee of this application, discloses a highly successful roll spacing and supporting structure including an elongated bar of expanded foam material, such as polystyrene, for use in palletizing rolls of material and protecting such rolls against damage in handling and shipment. Such elongated bar provides a plurality of spaced semi-cylindrical indentations along at least one of the surfaces for receiving rolls of material. Further, such an elongated bar of expanded foam material includes a plurality of recesses located within or adjacent to the side portions of the semi-cylindrical indentations to provide flexural cushioning. The bars of the Bell patent permit limited relative movement among the rolls of the stack while, at the same time, are of sufficient strength to prevent crushing and collapse of the stack. Also, the Bell patent discloses one embodiment which provides an integral lip along the outside edge of a semi-cylindrical indentation of a supporting bar to protect an otherwise exposed end of a material roll from damage.
In use, the elongated bars of the Bell patent may be placed between the bottom layer of rolls and the supporting pallet, between each layer of rolls in the stack, and on top of the stack. In one form of stacking arrangement, each layer contains a number of rolls of material arranged in parallel and axial orientation. The supporting bars may be arranged parallel to one another and spaced apart with the end portions of each roll supported in a semi-circular indentation provided by adjacent spaced bars.
The bars located in the interior of a stack as disclosed in the Bell patent receive and support the ends of axially adjacent rolls. In other words, a semi-cylindrical indentation provided by an interiorly located bar may be required to support the end portions of two rolls of material. Movement of the rolls within the stack has been minimized by securing a palletized stack with strapping and stretch wrap film.
The elimination of strapping from a pallet containing a multi-layer stack under certain loading configurations has been found to cause alignment problems within the stack because of vibrations of the type experienced during shipping and handling. Slight movements between the components of the stack may be caused by tilting, jarring, or similar forces encountered in shipping, which might result in either a roll or a supporting bar shifting within the stack. If such movement becomes large enough, the relative axial displacement of a roll may cause it to drop off a supporting bar. Alternatively, such movement may cause the rolls to be pushed together which might cause damage to the roll ends. The invention set forth herein provides a solution to these problems.